Here is a methodical program to test, correct and adjust the Rover SD1 Efi System that has gained an undeserved reputation for unreliability. On many cars, this is wholly due to long term neglect, lack of cleanliness and poor maintenance.

It is possible to use a scattergun approach to testing but the chances of hitting the right solution are significantly reduced. The sequence recommended in the PDF link below offers a good chance of quickly solving problems. Also, bear in mind that there may be more than one fault present, thus, completing the whole program offers the best probability of curing them all.

Before even considering testing and/or replacing components, be aware that the vast majority of Rover SD1 Efi System faults are caused by electrical wiring/connection faults and/or rogue air leaks into the inlet manifold usually via the plenum chamber and its connecting hoses/pipes.

The document describes a test process in just six pages with no illustrations. If, after these simple checks, idle speed, driving or drivability problems persist then a more serious review of system components is needed. In this case, obtain the comprehensive illustrated manual which explains how the system works or read the detailed individual component descriptions here:

Which-ever you decide please appreciate, despite its electronic heartbeat, the Rover SD1 Efi system isn’t rocket science and the supporting components are simple to understand/diagnose and the best option for the home mechanic is to study the available material to see how the components interact with each other to make the system work. Given just a reasonable understanding provides a good opportunity to rectify the performance of an afflicted Efi system.